Lysophosphatidylcholine facilitates the pathogenesis of psoriasis through activating keratinocytes and T cells differentiation via glycolysis

Background: Although abnormal metabolism plays a critical role in the pathogenesis of psoriasis, the details are unclear. Objectives: Here, we identified to explore the role and mechanism of lysophosphatidylcholine (LPC) on the pathogenesis of psoriasis. Methods: The level of LPC in plasma and skin lesions and the expression of G2A on skin lesions of psoriasis patients were detected by enzyme-linked immunosorbent assay, liquid chromatography-tandem mass spectrometry, or immunohistochemistry, respectively. The glycolysis in the skin lesions of imiquimod (IMQ)-induced psoriasis-like mouse model was detected by extracellular acidification rate. LPC was subcutaneously injected into IMQ-treated mouse ears, and the phenotype as well as the glycolysis were evaluated. Exploring the effects and mechanism of LPC on keratinocytes and CD4(+) T cells by culturing primary keratinocytes and CD4(+) T in vitro. Results: We found that LPC was significantly increased both in the plasma and skin lesions of psoriatic patients, while G2A, exerting an essential role in LPC-inducing biological functions, was increased in psoriatic lesions. The abundance of LPC was positively correlated with glycolytic activity in the psoriasis-like mouse model. LPC treatment facilitated psoriasis-like inflammation and glycolytic activity in skin lesions. Mechanistically, the LPC/G2A axis significantly triggered glycolytic activity and produced inflammatory factors in keratinocytes, and blockade of glycolysis abrogated LPC-induced expression of inflammatory mediators in keratinocytes. LPC activated STAT1, resulting in recognition and binding to the promoters of GCK and PKLR, which are glycolytic rate-limiting enzymes. Furthermore, the LPC/G2A axis directly benefited Th1 differentiation, which was dependent on LPC-induced glycolytic activity. Notably, LPC indirectly facilitated Th17 differentiation by inducing the secretion of IL-1b in keratinocytes-T cells coculture system. Conclusions: Taken together, our findings revealed the role of the LPC/G2A axis in the pathogenesis of psoriasis; targeting LPC/G2A is a potential strategy for psoriasis therapy.